Impact of fibroblast cell density on the material parameters of thin artificial human skin in the terahertz band

This paper presents the material parameters of collagen gel and dermal equivalents with different fibroblast cell densities in a Terahertz (THz) band from 0.2 THz to 1.5 THz. It is shown that collagen gel without cells has much higher refractive index and absorption coefficient than dermal equivalents, while the parameters of dermal equivalents slightly decrease with cell density. It denotes that the material parameters at the THz band is not only dependent on the water concentration but also their intrinsic biological features. The obtained results help understand the interaction of the THz wave with biological tissues and the diversity of material parameters of real human skin.